Forum home The potting shed

RHODODENDRON DIEBACK

I have often read posts in the forum that I've found incredibly helpful but I have never actually posted. I usually find that someone here has the answer without me having to, however in this case I fear the culprit causing my rhododendron dieback could be a couple of offenders so I was wondering if you could help me. 
I have attached a few images of a rhododendron and an azalea which are positioned in a South facing garden but are shaded by a tall fence and the rear wall of the house. They grew happily here for many years however I noticed that they started to experience die back last year which I put down to an over eager clematis that had started to tangled through their branches. In spring of this year, I dug up the offending clematis and repositioned it at the front of the house. I was hoping the 2 shrubs would recover once it had been removed, however as you can see the only signs of new growth are on the unaffected branches.
I am now concerned that the dieback is being caused by something else. The azalea's leaves are showing symptoms of a possible fungal infection. I am no expert so wondered if you could diagnosis the issue from the provided photographs and possibly advise the best way to help these plants to recover, presuming I haven't left it too late.

Many thanks 

Kate.


Posts

  • Pete.8Pete.8 Posts: 11,126
    Hi Kate
    The first thing that springs to mind of course is a lack of water, but the surrounding plants seem happy enough so I'm guessing you've kept the area well watered. It's between a fence and a wall so rain will be in short supply at the best of times.
    So long as you soil is suitable for them  - somewhere between neutral to acidic they should be ok assuming the roots haven't dried out.
    The only other thing I can think of is sunburn.
    You may be best waiting until Spring and see where new growth comes from then you can prune back any dead bits.
    In the mean time keep up with the watering

    Billericay - Essex

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Thanks Pete
    Firstly I should say that I live in Scotland so I'm in the fortunate position that watering isn't really an issue. During the really hot spell I did give everything a thorough drenching but as both these shrubs put on their growth in spring and we hadn't had the Mediterranean temperatures by then, I had ruled out the soil being too dry. At that time of year the soil surrounding the shrubs is blanketed with lily of the valley and anemone so the soil stays really quite moist with very little evaporation. My big concern is that this dieback started to appear last summer at which time I had considered sunburn or scorch but with no sign of regrowth this season I'm concerned what might be going on is an attacking phomopsis or similar fungus. If I leave that unattended could I run the risk of losing these plants completely.....or is this a case of me having 'Dr Googled' my plants? 😆 I know  these diseases usually take hold because of other stress factors so soil conditions may be a factor along with watering and  maybe overcrowding. I was thinking of scraping back the bark to see if there is any green and cutting down past that, digging out the top layer of soil, relaying topsoil and dressing with bark or is that premature and overkill? 
    Let me know your thoughts..

    Thanks

    Kste

  • Pete.8Pete.8 Posts: 11,126
    I suspect there's an element of stress involved along with some hot sun.
    Maybe the soil lower down where the majority of the roots are for those shrubs is dry. It does look mostly like a lack of water and strong sun.
    Sights such as in your photo are very common around here this year.
    Many front gardens have dead shrubs and parched lawns.

    Try the bark test - starting at the top and working down, then cut off the dead bits as you suggest.
    I doubt it's anything to do with the soil, so I wouldn't start removing and replacing soil. You'll cause a lot of root damage too and in the unlikely event there is something in the soil, it'll likely still be there somewhere.

    There's not much else you can do other then keep them well watered and hope for the best next year. If you can give them a good mulch that will help.
    Don't be tempted to feed them until they're recovering.

    I don't have any azaleas but I do have a huge rhododendron and that can be cut back almost to the ground and it'll happily re-shoot in no time.

    Billericay - Essex

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Pete
    You're a star! Thank you! I really wasn't sure if I would be doing more harm than good. I'd hate to have killed them off with ignorance. I'll do as advised and hope for regrowth next year and post images next spring to show progress. Hopefully it works and we see rejuvenation. These plants are absolutely glorious in flower. I'd have been heartbroken to have lost them.
    Many thanks again!

    Kate.
  • Pete.8Pete.8 Posts: 11,126
    Good luck Kate - I'll keep everything crossed for you and hope they come back full of vigour and flowers next year :) 

    Billericay - Essex

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
Sign In or Register to comment.